摘要
以软土地区高速铁路无砟轨道路基段的地面振动问题为例,通过运用车辆-轨道耦合动力学理论和有限元方法,计算分析了速度为350 km/h的高速列车通过无砟轨道路基段引起的地面竖向振动时域、频域特征及其随距离的衰减规律,并与实测结果进行了对比。研究结果表明:在距离轨道不同位置处,计算与实测得到的地面振动加速度时域峰值的吻合度较好,20 m之前地面振动时域峰值衰减速率较快,而20 m以后其衰减速率开始减缓。通过对比地面振动1/3倍频程计权加速度级发现,计算与实测结果间的主频带振级相差不到5 dB。此外,从地面振动计权加速度级随距离的衰减规律可知:列车速度为350 km/h时的软土区高速铁路无砟轨道路基段周边50 m范围内的地面振动计权加速度级均大于65 dB,对人们正常生活的影响不可忽视。
According to the ground vibration test at non-ballasted track on embankment of the high- speed railway in a soft soil district, this paper presents a method in investigating ground-born vibration induced by high-speed railway. It was based on vehicle-track coupled dynamics and FEM method, and a train-track coupled vertical model and 2D FEM model were established. The equivalent load on subgrade surface was obtained from the train-track coupled vertical model, and then applied onto FEM model. The investigation shows the following results. The simulation time-domain peaks of vertical ac- celeration of ground vibration at every measuring point are in good agreement with the field measure-ment. As distance increases, time-domain peaks attenuate quickly within 20 m from railway center- line, while getting slower after that. One-third octave band results of frequency-weighted vertical ac- celeration levels generally, agree well with the test results in the center frequency between 1 Hz and 64 Hz. There is only 5 dB difference in their main frequency bands. From the attenuation of frequency- weighted vertical acceleration levels with distance from track centerline, frequency-weighted vertical acceleration levels are more than 65 dB within 50 m, which should get people＇ s attention.
出处
《重庆理工大学学报（自然科学）》
CAS
2013年第9期53-58,共6页
Journal of Chongqing University of Technology：Natural Science
基金
四川省科技支撑计划项目(2011GZ088)
国家自然科学基金青年基金资助项目(50838006
51008257)
